When to Plant Sunflower in Steele County, ND
Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.
Steele County, North Dakota is in USDA Zone 4a. The average last spring frost is May 11 and the first fall frost is October 1, giving you a growing season of approximately 143 days.
At an elevation of 624 feet, Steele County receives approximately 21.9 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Sunflower to ensure they mature before fall.
Steele County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Sunflower Planting Timeline — Steele County, ND
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 20 | Apr 20 – May 4 |
| Transplant Outdoors | May 25 | May 25 – Jun 8 |
| Direct Sow | May 25 | May 25 – Jun 15 |
| Bloom | August 17 | Aug 17 – Oct 12 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 4a
📆 Growing Season
143 days in Steele County
Growing Tips for Steele County
Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Steele County, ND?
Steele County is in Zone 4a with an average last frost of May 11. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Steele County, ND?
Steele County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 11 and first fall frost is October 1.
Your Steele County Garden Planner — Free
A 22-page printable planner built for Steele County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.